In recent years, as new transportation system other than buses or trains, some of innovative transportation systems have garnered attention. One of the transportation systems is known in which a vehicle having wheels formed from rubber tires runs along a central guide rail.
As for this type of vehicle, for example, there is one disclosed in the following PTL 1. A running device of the vehicle described in PTL 1 is provided with a plurality of guide wheels that are aligned in the vehicle width direction to form pairs so as to grip a center guide rail, a frame provided so as to be rotatable about an axis perpendicular to the floor surface of a vehicle body, and a steering link mechanism that changes the steering angle of wheels in association with the rotation of the frame about a rotation axis. Each guide wheel is attached to the frame so as to be rotatable about a guide wheel shaft parallel to the rotation axis. This running device has two gripping pairs that are arranged in the front-and-rear direction. That is, this running device has a total of four guide wheels.